Do sodium-ion batteries offer a solution to the geopolitical instability associated with ev production?

Recent surges in demand for Electric Vehicles (EVs) reflect a growing environmental consciousness, a desire to mitigate the adverse impacts of air pollution and climate change, and our growing carbon footprints. The Paris Declaration on Electro-Mobility and Climate Change recognises that transport contributes 23% of the current global energy-related greenhouse gas emissions. The document therefore provides an ambitious framework to electrify global transport networks: it references forecasting from the International Energy Agency and outlines plans for EV production to represent 35% of global vehicle sales by 2030. Indeed, the annual projected sales of EVs are set to exceed 40 million vehicles by 2028. As such, the demand for lithium-ion battery cells is unprecedented. These batteries currently represent the bedrock of EV production and are seen as a route out of our traditional reliance on fossil fuels. However, lithium-ion batteries are not without their faults as supply chains are frequently linked to geopolitical tension and ESG issues. This article will therefore explore an emerging technology, sodium-ion batteries, and evaluate the potential of these new fuel cells in navigating the complex landscape of EV production. 

Lithium-ion batteries have changed the world. The technology has not only put smartphones, laptops, and wireless headphones into the pockets and onto the desks of billions, but it has also found a foothold in the EV industry where it looks poised to play a big role in the green transition. The demand for lithium more than tripled between 2015 and 2020 and is expected to grow by more than 500% to reach 2.2 million tonnes by 2030. Supporting further progress in developing the EV industry will require significant investment into both the mining and processing of lithium. 

However, such growth has the potential to create problems, chief among them are the global dependency issues linked with the use of lithium in fuel cells and batteries. China currently dominates the global battery industry. Its flagship producers CATL and BYD enjoy more than 50% of the global market share and have made significant steps in lowering the capital costs at their factories to less than USD 60mn/GWh of batteries produced. Additionally, this dominance shows few signs of slowing; CATL’s research and development budget has more than doubled in the last year to 2bn USD. From a Western perspective, Chinese dominance prompts questions regarding the consequences of geopolitical dependency on Chinese supply. Given that Western countries (especially those in Europe) have spent much of the last two years trying to reduce their dependence on Russian fossil fuels, the need for energy security among politicians has never been clearer. These concerns are not merely theoretical; China has already shown its geopolitical clout in the battery industry by instigating national-security restrictions in October on the export of graphite.

Concerns have also been raised internationally about the broader implications of lithium mining and its negative environmental effects. The most prevalent method of extracting lithium from natural brines in South America has severely depleted the natural aquifers that local communities and ecosystems depend on. Some estimates go as far as to predict that 2.2 million litres of water are required to produce one ton of lithium. The most effective lithium-ion batteries in terms of energy density (frequently abbreviated to NMC) also require cobalt. This is a transition metal that is mined in extremely poor conditions almost entirely in the Democratic Republic of Congo.  

To address the geo-political and environmental issues associated with the production of lithium-ion batteries for EVs, sodium-ion batteries are increasingly recognized as a prospective solution. Sodium is the sixth most abundant element in the Earth’s crust and therefore, unlike lithium, stands out as a resource less susceptible to geopolitical issues of supply and demand. Furthermore, these batteries could also eliminate the ethical concerns associated with cobalt mining for EV production in countries such as Democratic Republic of Congo. This is because transition metals are not required in many sodium-ion batteries. The use of sodium batteries may also present advantages in safety and some benefits in performance. Sodium cells are non-flammable and resistant to both explosions and short circuits. These batteries also exhibit robust performance across a wide temperature range, operating effectively between -20°C and 60°C. 

Nevertheless, sodium-ion technology comes with its own set of drawbacks that demand careful consideration. Firstly, what sodium has in natural abundance compared with its chemical cousin it lacks in efficiency; sodium atoms are larger, meaning that a sodium-ion battery is naturally bigger and heavier. Although recent developments in energy density do show encouraging signs, the energy density of sodium-ion batteries is still relatively low, between 140Wh/Kg and 160Wh/Kg compared to lithium-ion batteries’ 180-250Wh/Kg. Moreover, current trends show that the development of sodium-ion batteries may not be able to adequately address the geo-political issues of Western reliance on Chinese manufacture in the battery industry. Research and development (R&D) of sodium-ion batteries is itself being pioneered by China. According to Benchmark Mineral Intelligence, 36 Chinese companies are either making or carrying out R&D on sodium-ion technology. CATL announced the world’s first sodium battery for electric vehicles in 2021 and BYD has been similarly proactive: the Seagull hatchback will soon run on sodium-ion fuel cells. In total, Chinese firms have 34 sodium-ion factories built, being built, or announced inside the country. 

China’s pursuit of sodium-ion battery production is significant. Not only does it show the country’s desire to maintain its position as the global leader in battery production, but it also demonstrates that sodium-ion batteries are being taken seriously as an alternative to batteries made with lithium. Indeed, sodium-ion batteries do look attractive and improvements in energy densities have the potential to alleviate supply pressure and calm geo-political tensions. However, Western countries could forsake these advantages if they continue to allow China to dominate the research, development, and manufacturing of new technology in this industry.